Bruno Mars' had ''creative freedom'' on 'Unorthodox Jukebox'.

The 'Locked out of Heaven' singer is preparing the release of his second album, and enjoyed skipping between different genres on each track of the album.

He told Billboard magazine: ''This is me going into the studio and recording and writing whatever I want. This album represents my freedom

''I listen to a lot of music and I want to have the freedom and luxury to walk into a studio and say, 'Today I want to do a hip-hop, R&B, soul or rock record.'''

The 26-year-old singer said his desire to keep changing his sound between songs wasn't popular with record executives at the beginning of his career, when he was dropped by the Universal Motown label.

He added: ''I've had big record label presidents look me in the face and say, 'Your music sucks, you don't know who you are, your music is all over the place, and we don't know how to market this stuff. Pick a lane and come back to us.

''That was disgusting to me, because I'm not trying to be a circus act.''

'Unorthodox Jukebox' is released in December, but Bruno is working on the final mixes of the album right up until deadline as he wants to ensure he's completely happy with them, after never liking the final version of 'It Will Rain' from 'The Twilight Saga: Breaking Dawn Part 1' soundtrack, and always turns it off if it comes on the radio.

He explained: ''I felt like I was a mosquito singing. I don't want that to happen again.''